Overview
The LM3881MME/NOPB, produced by Texas Instruments, is a Simple Power Sequencer designed to control the power-up and power-down sequences of multiple power supplies. This device is particularly useful in avoiding latch conditions or large inrush currents that can affect system reliability. It features a tiny footprint, available in an 8-pin VSSOP package, making it suitable for a variety of applications where space is limited.
The LM3881 allows for the sequencing of three power supplies with adjustable timing, controlled by an external capacitor. It includes an enable pin and three open-drain output flags that sequentially release after individual time delays, ensuring a controlled startup and shutdown of the connected power supplies.
Key Specifications
| Parameter | Min | Max | Unit |
|---|---|---|---|
| VCC, EN, INV, TADJ, FLAG1, FLAG2, FLAG3 to GND | -0.3 | 6.0 | V |
| Junction Temperature | - | 150 | °C |
| Lead Temperature (Soldering, 5 s) | - | 260 | °C |
| Storage Temperature Range | -65 | 150 | °C |
| VCC to GND | 2.7 | 5.5 | V |
| Junction Temperature (Operating) | -40 | 125 | °C |
| Quiescent Current | - | 80 | µA |
| EN Pin Threshold | 1.0 | 1.22 | V |
| INV Pin VIH | 90% VCC | - | V |
| INV Pin VIL | 10% VCC | - | V |
| Flag Time Delay (TD1) | 10.8 ms | 12.0 ms | ms |
| Flag Time Delay (TD2, TD3) | 9.6 ms | - | ms |
Key Features
- Easiest Method to Sequence Rails: The LM3881 provides a simple and effective way to sequence multiple power supplies, avoiding latch conditions and large inrush currents.
- Power-Up and Power-Down Control: Controls the startup and shutdown sequences of three power supplies with adjustable timing.
- Tiny Footprint: Available in an 8-pin VSSOP package, making it ideal for space-constrained designs.
- Low Quiescent Current: Operates with a low quiescent current of 80 µA.
- Input Voltage Range: Supports an input voltage range of 2.7 V to 5.5 V.
- Output Invert Feature: Allows the logic of the output flags to be inverted using the INV pin.
- Timing Controlled by External Capacitor: Time delays are defined using an external capacitor.
Applications
- Security Cameras: Ensures controlled power sequencing in security camera systems.
- Servers: Used in server systems to manage power supply sequences effectively.
- Networking Elements: Suitable for networking equipment requiring controlled power-up and power-down sequences.
- FPGA Sequencing: Ideal for sequencing power supplies in FPGA-based systems.
- Microprocessor and Microcontroller Sequencing: Used in various microprocessor and microcontroller-based systems to manage power supply sequences.
- Multiple Supply Sequencing: General-purpose sequencing of multiple power supplies in various electronic systems.
Q & A
- What is the primary function of the LM3881?
The LM3881 is a Simple Power Sequencer designed to control the power-up and power-down sequences of multiple power supplies.
- What package options are available for the LM3881?
The LM3881 is available in an 8-pin VSSOP package.
- What is the input voltage range of the LM3881?
The input voltage range is from 2.7 V to 5.5 V.
- How are the time delays controlled in the LM3881?
The time delays are controlled by an external capacitor connected to the TADJ pin.
- Can the logic of the output flags be inverted?
- What is the quiescent current of the LM3881?
The quiescent current is 80 µA.
- What are some common applications of the LM3881?
- How does the LM3881 handle power-down sequences?
- What is the junction temperature range for the LM3881?
- Is the LM3881 suitable for high-temperature environments?
